Prong file and method of making same



Aug.241926.

- 1,597,387 G. A. OLSEN Paone FILE AND METHon oF MAKING SAME Filed oct. 1, 1924 Patented Aug. 24, 1921i,

UNIT i) ES GEORGE A. OLSEN, OF CHICAGO, ILLINOZS ASSQIJIGR TO ACOUNTING DEVICES CSM PANY, 0F CHICAGO, ILLNOIS, A CORPORATION GF ILLNOIS.

PRONG FILEAND METHOD 0F MAKING SAME.

Application filed October 1,'1924. Serial No. 741,077.

This invention relates to prong files and the like and to the method of making the saine which is fully described in the following specification and shown in the accompanying drawing, in Which:

Figure 1 is a top plan view of the back of a prong file embodying the'invention;

Fig. 2. is a side elevation of one of the back sections before the end pieces and prongs are secured thereto;

Fig. 3 is a transverse section on the line 3 of Fig. 1; and

Fig. i is an enlarged partial perspective of the upset end of the prong.

The` embodiment illustrated relates to prong files of the type shown and fully described in my Patent No. 1,500,630, and comprises the metal back for a prong file comprising tivo metal back sections 10 and 11 which are. of L-shape as shown in Fig. 3, the ends being offset at 10a and 11"L to accommodate the ears 12 and 13a of the end pieces 12 and 13, so that the outer surfaces of the ears 12a and 13EL will lie substantially fiush with the outer surfaces of the back sections 10 and 11. These end pieces are secured to the back sections by any suitable means such as spot Welding at 141.

The end pieces 12 and 13 overlap and are hingedly secured together by means of rivets 15. The end pieces are made arcuate at 16. The radius Vof the arc being swung above the center of the post 17 onto which a locking arm 18 is pivoted. Fingers 12b and 13b are formed on these end pieces so as to provide notches at the junction on these lingers with the arcuate portions 16. A. pin 19 is carried by the arm 1S and this is normally forced toward these notches by means of a spring 2O when therefore the bach sections are swung toward each other, the pin 19 rides up over the finger 12b and is pressed down into the notch by the spring 20, thereby blocking the tivo back sections in this closed position until it is released by pressing up on the pin 19.

Hinge plates'21'and 22 are secured to the back sections 12 and 13 by any suitable means such as spot Welding (not shown), the

upper edges of these sections havinginterrupted tubular portions 23 and 24 to Which the inner face of the back members 10 andv 11 so that it may be readily secured thereto by an electric Weld or the like. A notch 27 is formed in this flattened face of the prong 25 and al complementary projection 28 is formed in the back member so that the prong can be readily positioned by placing the notch 27 over the projection 28. This projection .is preferably pressed from the metal thereby leaving a. corresponding de# pression 29 in the outside of the back member as shown in Fig. 3. rlhe free ends of the prongs 25 are preferably round and fall in openings A30 in the opposite back member.

While i have .shown and described but a single embodiment of this invention, it is to be understood that it` is capable of many modifications. Changes therefore in the construction and arrangement may be made Which do not depart from the spirit anc` scope of the invention as disclosed in the appended claims.

I claim: l

1. In a prong iile, two opposing back sections hingedly connected together, a prong secured to one section, said prong having a depression on the surface of the prong touching said section, and a complementary projection on the adjacent surface of said section for accurately centering said prong While it is being secured thereon.

2. In a prong file, two opposing back sections hingedly connected together, a prong secured toone section, said prong having a flattened end and a depression on the surface of the prong touching said section, and a compiementary projection on the adjacent surface of said section for accurately centering said prong While it is being secured thereon. V i

In a prong file, two back sections hingedly securedtogether, a prong secured to one section, said prong having a notch on the surface of said prong in contact with said section,l and a complementary projection on the adjacent surface of said section for centering said prong, said prong being.

Welded to said section.

4L. In a prong file, two beck sections hing-Yr section, said prong having one end upset and flattened, Said iattened surface having a notch on the surface of said prong in contact with said section, and a complementary projection on the adjacent surfeceof said section for centering said prong, said prong being welded to said Section.

GEORGE A. oLenN. 

